Aluminium alloy



Patented Feb. 28,1933

UNITED STATES OTTO KAMIE'S, OF BERLIN, GEEK-ANY ALUMINIUM ALLOY no Drawing. Application filed ma a, 1930,

The new alloy possesses, in comparison with the known aluminium alloys, a number of valuable properties and is especially distinguished by high proofness against tarnishing. The new alloy comprises preferably an addition of vanadium or palladium, and for certain purposes a further addition of nickel. Aluminium nickel alloys have become known, which however do not have the additions of this new alloy and therefore do not possess the valuable properties of the same.

A method of: increasing proofness of the new alloy forms part of the invention. This method is characterized in that the alloy, in liquid state, is submitted, at a temperature of approximately 750 0., to a refining and, purification by strontium chloride. The strontium chloride is preferably added, after the liquid metal has been left standing for about 5 to 10 minutes without being touched, in an aluminium cartridge at the bottom of the liquid metal, whereupon the bath is thoroughly stirred several times and each time is carefully skimmed.

The new alloy is extraordinarily proof against tarnishing and shows no inclination to become black, in contrast to pure silver alloys which, when used, become black. This inconvenience of the pure silver alloys exeludes their use for numerous purposes. The new alloy can further be easily treated and is at least equal, and in many respects even superior, to the commonly used silver-copper-aluminium alloys as regards color, resistance and hardness. It is proof against tar nishing, for instance in sulphurous atmospheres, and superior in this respect to sterling silver and pure silver. The alloy can be cast to casting, chill-casting and extrusion-casting, and then shows resistances, which are equal to those of brass in cast and rolled condition. Theallo possesses also extraordinary adaptabihty or heavy drawings and is suitable to be used in the industries engaged in the prothe tarnishing the finest wall thicknesses, as sand- Serial No. 450,877, and in Germany Iarch 8, 1980.

duction of vessels of any kind, of articlesof decoration and for lighting purposes. It possesses an extraordinarily uniformly fine crystalline structure. The semi-manufactured articles made of the alloy can be rolled out in any lengths and widths and they do not smear, when being worked up.

The composition of the new alloy is preferably as follows: copper 2 to 5% or nickel 0.2 to- 0.8% or copper and nickel in a total quantity of about 2 to 5%, silver 0.2 to 1%, thallium 0.02 to 0.2%, vanadium or palladium about 0.1%, the remainder commercial qualityaluminium with the usual iron percentage tolerances.

I claim:

1. A light metal alloy containin 0.2 to 4 vanadium or palladium upto 0.1%, the remainder principally aluminium.

4. A light metal alloy containing 0.2 to 1.0% of silver, 2 to 5% of copper, 0.02-to 0.2% of thallium, and an appreciable amount of vanadium up to 0.1%, e remainder principally aluminium. 5. A light metal alloy containing 0.2 to

1.0% of silver, 2 to 5% of copper, 0.02 to 0.2% of thallium, an appreciable amount of vanadium up to' 0.1%, and 0.2 to 0.8% of nickel,the remainder principally aluminium.

In testimonywhereof I aflix my signature.

. OTTO. KAMPS. 

